Many finite elements used in structural analysis possess deficiencies like shear
locking, incompressibility locking, poor stress predictions within the element domain,
violent stress oscillation, poor convergence etc. An approach that can probably
overcome many of these problems would be to consider elements in which the
assumed displacement functions satisfy the equations of stress field equilibrium. In
this method, the finite element will not only have nodal equilibrium of forces, but also
have inner stress field equilibrium. The displacement interpolation functions inside
each individual element are truncated polynomial solutions of differential equations.
Such elements are likely to give better solutions than the existing elements.In this thesis, a new family of finite elements in which the assumed displacement
function satisfies the differential equations of stress field equilibrium is proposed. A
general procedure for constructing the displacement functions and use of these
functions in the generation of elemental stiffness matrices has been developed. The
approach to develop field equilibrium elements is quite general and various elements
to analyse different types of structures can be formulated from corresponding stress
field equilibrium equations. Using this procedure, a nine node quadrilateral element
SFCNQ for plane stress analysis, a sixteen node solid element SFCSS for three
dimensional stress analysis and a four node quadrilateral element SFCFP for plate
bending problems have been formulated.For implementing these elements, computer programs based on modular concepts
have been developed. Numerical investigations on the performance of these elements
have been carried out through standard test problems for validation purpose.
Comparisons involving theoretical closed form solutions as well as results obtained
with existing finite elements have also been made. It is found that the new elements
perform well in all the situations considered. Solutions in all the cases converge
correctly to the exact values. In many cases, convergence is faster when compared
with other existing finite elements. The behaviour of field consistent elements would
definitely generate a great deal of interest amongst the users of the finite elements.

Description:

Department of Ship Technology, Cochin University of Science and Technology

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Wilson,P R; Dr.Nair, K N(Cochin University of Science And Technology, October , 1981)

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Today India is seeking a speedy transformation of her semi-stagnant economy to a dynamic one by means of economic planning in a democratic set up. In the context of this growth oriented endeavour public sector has a vital role to play. After three decades of planned development,
it has become important that India must make fresh appraisals on the role of public sector in the economic renaissance of the country. Almost no comprehensive study has been made on
this vital segment of the economy vis-a-vis the growth economics. This study is an attempt to fill this need in a very modest way. It presents the subject in a new perspective. An earnest attempt is made to reveal the critical problems inhibiting the growth of the public sector from a new angle which focusses the spot-light on the economics of development.

Description:

School of management studies, Cochin University of Science And Technology

Time resolved optical emission spectroscopy is employed to study the expansion
dynamics of C2 species in a graphite plasma produced during the Nd : YAG ablation. At low laser
fluences a single peak distribution with low kinetic energy is observed. At higher fluences a twin
peak distribution is found. It has been noted that these double peak time of flight distribution splits
into a triple peak structure at distances >_ 17mm from the target surface. The reason for the
occurrence of multiple peak is due to different formation mechanisms of C2 species

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Warships are generally sleek, slender with V shaped sections and block
coefficient below 0.5, compared to fuller forms and higher values for commercial
ships. They normally operate in the higher Froude number regime, and the
hydrodynamic design is primarily aimed at achieving higher speeds with the
minimum power. Therefore the structural design and analysis methods are
different from those for commercial ships. Certain design guidelines have been
given in documents like Naval Engineering Standards and one of the new
developments in this regard is the introduction of classification society rules for
the design of warships.The marine environment imposes subjective and objective uncertainties
on ship structure. The uncertainties in loads, material properties etc.,. make
reliable predictions of ship structural response a difficult task. Strength, stiffness
and durability criteria for warship structures can be established by investigations
on elastic analysis, ultimate strength analysis and reliability analysis. For analysis
of complicated warship structures, special means and valid approximations are
required.Preliminary structural design of a frigate size ship has been carried out . A
finite element model of the hold model, representative of the complexities in the
geometric configuration has been created using the finite element software NISA.
Two other models representing the geometry to a limited extent also have been
created —- one with two transverse frames and the attached plating alongwith the
longitudinal members and the other representing the plating and longitudinal
stiffeners between two transverse frames. Linear static analysis of the three models have been carried out and each one with three different boundary
conditions. The structural responses have been checked for deflections and
stresses against the permissible values. The structure has been found adequate
in all the cases. The stresses and deflections predicted by the frame model are
comparable with those of the hold model. But no such comparison has been
realized for the interstiffener plating model with the other two models.Progressive collapse analyses of the models have been conducted for the
three boundary conditions, considering geometric nonlinearity and then
combined geometric and material nonlinearity for the hold and the frame models.
von Mises — lllyushin yield criteria with elastic-perfectly plastic stress-strain curve
has been chosen. ln each case, P-Delta curves have been generated and the
ultimate load causing failure (ultimate load factor) has been identified as a
multiple of the design load specified by NES.Reliability analysis of the hull module under combined geometric and
material nonlinearities have been conducted. The Young's Modulus and the shell
thickness have been chosen as the variables. Randomly generated values have
been used in the analysis. First Order Second Moment has been used to predict
the reliability index and thereafter, the probability of failure. The values have
been compared against standard values published in literature.

Description:

Department of Ship Technology,
Cochin University of Science and Technology

Fine particles of cobalt ferrite were synthesized by the sol–gel method.
Subsequent heat treatment at different temperatures yielded cobalt ferrites
having different grain sizes. X-ray diffraction studies were carried out to
elucidate the structure of all the samples. Dielectric permittivity and ac
conductivity of all the samples were evaluated as a function of frequency,
temperature and grain size. The variation of permittivity and ac conductivity
with frequency reveals that the dispersion is due to Maxwell–Wagner type
interfacial polarization in general, with a noted variation from the expected
behaviour for the cold synthesized samples. High permittivity and
conductivity for small grains were explained on the basis of the correlated
barrier-hopping model

Nanoparticles of nickel ferrite have been synthesized by the sol–gel method and the effect of grain size on its structural and magnetic
properties have been studied in detail. X-ray diffraction (XRD) studies revealed that all the samples are single phasic possessing the
inverse spinel structure. Grain size of the sol–gel synthesized powders has been determined from the XRD data and the strain graph. A
grain size of 9 nm was observed for the as prepared powders of NiFe2O4 obtained through the sol–gel method. It was also observed that
strain was induced during the firing process. Magnetization measurements have been carried out on all the samples prepared in the
present series. It was found that the specific magnetization of the nanosized NiFe2O4 powders was lower than that of the corresponding
coarse-grained counterparts and decreased with a decrease in grain size. The coercivity of the sol–gel synthesized NiFe2O4 nanoparticles
attained a maximum value when the grain size was 15nm and then decreased as the grain size was increased further.

The whale shark (Rhiniodon typus Smith) is an under exploited species and it is
mainly caught for its liver oil . The processing of shark fin for rays is reported here .
The fins have a high content of rays . The yield of fin rays from undried fins ranged
from 0 .53 to 4 .40 percent with maximum ray content in the lower lobe of caudal fin .
The physical and chemical characteristics of the rays are reported . The total nitrogen
content is about 15 to 16 percent (dry weight basis)

This paper describes the first use of polystyrene-supported
poly(amidoamine) (PAMAM) dendrimers as heterogeneous
basic organocatalysts for carbon–carbon bond formation.
Polystyrene-supported PAMAM dendrimers of first, second
and third generations have been used as reusable base catalysts
in Knoevenagel condensations of carbonyl compounds
with active methylene compounds. The reactions proceed in short periods of time and with 100% selectivity. This novel
catalyst eliminates the use of aromatic and halogenated solvents,
as well as complex purification processes. The catalysts
can be recycled ten times.

Joyni,Jacob M; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, January , 2012)

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A general introduction to the problems faced in the shrimp culture due to waste formation and its consequent environmental hazards and production problems of Giant tiger shrimp, Penaeus monodon is highlighted by the author in this thesis. The objective of the present work was to assess the potential of brackish water finfish to improve bottom soil conditions and
thereby increase the growth and production of Penaeus monodon. The salient findings of the present study are summarized in chapter 7. This is followed by the references cited in the thesis and list ofpublications originated from the present study.

Description:

School of Industrial Fisheries, Cochin University of Science and Technology

Elasmobranchs comprising sharks, skates and rays have traditionally formed an important fishery along the Indian coast. Since 2000, Indian shark fishermen are shifting their fishing operations to deeper/oceanic waters by conducting multi-day fishing trips, which has resulted in considerable changes in the species composition of the landings vis- a-vis those reported during the 1980’s and 1990’s. A case study at Cochin Fisheries Harbour (CFH), southwest coast of India during 2008-09 indicated that besides the existing gillnet–cum- hooks & line and longline fishery for sharks, a targeted fishery at depths >300-1000 m for gulper sharks (Centrophorus spp.) has emerged. In 2008, the chondrichthyan landings (excluding batoids) were mainly constituted by offshore and deep-sea species such as Alopias superciliosus (24.2%), Carcharhinus limbatus (21.1%), Echinorhinus brucus (8.2%), Galeocerdo cuvier (5.4%), Centrophorus spp. (7.3%) and Neoharriotta pinnata (4.2%) while the contribution by the coastal species such as Sphyrna lewini (14.8%), Carcharhinus sorrah (1.4%) and other Carcharhinus spp. has reduced. Several deep-sea sharks previously not recorded in the landings at Cochin were also observed during 2008-09. It includes Hexanchus griseus, Deania profundorum, Zameus squamulosus and Pygmy false catshark (undescribed) which have been reported for the first time from Indian waters. Life history characteristics of the major fished species are discussed in relation to the fishery and its possible impacts on the resource

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The article examines the commodity chain trap of marine fishery in Kerala, at both material and value terms, and its
ramifications in the globalised fishery chains. The marketing chains both material and value, are very complex in
nature since they involve many types of markets and large number of intermediaries and participants. The article also
scrutinizes the sensitivity of consumers’ and country’s responses in terms of dietary and hygienic standards relating
to seafood trade. In addition, it discusses the devastating effect about the recent stipulations like the US Bio-
Terrorism Act and Shrimp anti-dumping duty on the Kerala fishery products

The spoilage characteristics of bacterial strains were studied by growing them
at 28 _+ 2 °C in agar and broth media prepared with sterile fish and prawn flesh
homogenates. The percentage of spoilers found among the bacterial isolates
tested, as shown by odour production and halo zone formation, was independent
of the source of flesh used. Indole and fluorescent pigment production were
also observed in the broth. Pseudomonas, Vibrio and Acinetobacter exhibited
faster growth in flesh media than in the usual artificial media. Decrease of protein
and lipid concentration in the clear zone of agar media suggests the utilization
of the available substrate by spoilage bacteria.

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Manojkumar, T G; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, March 22, 2006)

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This thesis entitled Fish habitats and species assemblage in the selected rivers of kerala and investigation on life history traits of puntius carnaticus (JERDON,1849). Ecology is a new and exceedingly complex field of study, even though its concept was recognized by the Apostles in their use of the phrase ‘all flesh is grass.central role to play both in order to understand better the biodiversity phenomenon and to be able to draw up clear guidelines for careful resource management. In a review by WWF, IUCN and UNEP on the ways of conserving genetic diversity of freshwater fish it was recommended that the best way to conserve species diversity is to conserve habitat.The habitat studies in freshwater ecosystems are very essential for the proper understanding and management of human impact on fish diversity, to study the relationship between habitat variables and fish species assemblage structure, quantification of ecosystem degradation, habitat quality and biotic integrity of the ecosystems, development of habitat suitability index (I-ISI) models and classification of river reaches based on their physico-chemical properties. Therefore in the present study an attempt was made to assess the biodiversity potential and the relationship between habitat variables and fish species assemblage structure in six major river systems of Kerala which would be very useful in impressing upon the seriousness of habitat degradIn the present study, in Kabbini river system 15 locations encompassing between 721 946m above MSL were surveyed.ation and biotic devastation undergone in the major river systems of Kerala.During the present study the Habitat Quality Score (HQ) developed by the Ohio EPA was applied for the first time in India.The result of the present study revealed that, among various variables analysed, altitude has a very significant influence in deciding the fish diversity in six major river systems of Kerala. The fish diversity studied on the basis of Shanon-Weiner and Simpson diversity indices revealed that even though some minor variations occur with the suitability and complexity of habitats, the altitude showed inverse relationship with fish diversity.The present study revealed that the National Policy on the interlinking of rivers would permanently alter the HSI indices of the above mentioned fish species, which are now solely protected by the individuality of the rivers where their limited occurrence was notice.

Description:

School of Industrial
Fisheries,Cochin University of Science and Technology

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Rajasenan, D; Dr.Sankaranarayanan, K C(Cochin University Of Science And Technology, March 2, 1987)

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importance of fishing and other allied industries
in the economy was realised only very recently. Consequently
only very few studies are available on the subject. Here an
attempt is made to survey the available literature on the
subject.

Description:

Department Of Applied Economics
Cochin University Of
Science And Technoogy

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Result of the study on traditional traps in the inland waters of three northern districts viz,
Kasargod, Kannur and Kozhikode in Kerala state during 2003-2004 is presented. Mainly six
types of traps are found in operation. Chempally koode is a rectangular bamboo trap with"
D" shape in cross section operated without bait in some rivers of Kannur and Kasargod.
Bamboo screen barriers are almost completely replaced with durable HDPE net screen to
make handling easy. Thottil vala is a unique aerial trap operated from the dam in Pazhassi reservoir during monsoon to catch big fishes jumping against flowing water.

Invertase was immobilized on acid activated montmorillonite via two independent procedures, adsorption and covalent binding. The immobilized enzymes were characterized by XRD, NMR and N2 adsorption measurements and their activity was tested in a fixed bed reactor. XRD revealed that the enzyme was situated on the periphery of the clay and the side chains of different amino acid residues were involved in intercalation with the clay matrix. NMR demonstrated that tetrahedral Al was linked to the enzyme during adsorption and the octahedral Al was involved during covalent binding. Secondary interaction of the enzyme with Al was also observed. N2 adsorption studies showed that covalent binding of enzymes caused pore blockage since the highly polymeric species were located at the pore entrance. The fixed bed reactor proved to be efficient for the immobilized invertase. The optimum pH and pH stability improved upon immobilization. The kinetic parameters calculated also showed an enhanced efficiency of the immobilized systems. They could be used continuously for long period. Covalently bound invertase demonstrated greater operational stability.